In a power supply device for a vehicle, in order to make power supplied to a motor driving the vehicle big, output voltage is increased by a lot of rechargeable secondary battery cells connected in series. One instance of a conventional power supply device is shown in an explored perspective view of FIG. 22. In the power supply device shown in this figure, plural battery cells having a rectangular box shape are stacked, and end plates 223 are disposed at the end surfaces of the stacked member. Binding bars 224 bind the end plates 223 each other. The binding bars 224 are made by bending metal boards. Further, a bus bar holder having insulation property is fixed on the upper surface of the stacked member. The bus bar holder of insulation property is sandwiched between the upper surface of the stacked member of the battery cells 221 and the binding bar 224 made of metal, and insulates the battery cells 221 bound by the binding bars 224 from each other without their outer cans conducting. Additionally, a circuit board or the like is fixed on the upper surface of the bus bar holder. The circuit board includes a detecting circuit which detects a cell voltage of each of the battery cells, a circuit which carries out various controls, or the like. Therefore, at the time of assembling the power supply device, after the bus bar holder is fixed in a state that the battery cells 221 are stacked in advance, the binding bars 224 bind the stacked member.
However, such an assembling procedure has a problem that working efficiency is decreased. Namely, in order to fix the bus bar holder, it is necessary to fix the bus bar holder in a state that electrode terminals of the battery cells are coupled by the bus bars. Accordingly, as shown in FIG. 23, both end surfaces of the stacked member are pressed by jig JG, and while this state is held, the bus bar holder is put on the upper surface, and the bus bars are fixed each other by welding or screw. After that, the binding bars 224 are set, and the pressing of the jig JG is released, and then the binding bars 224 are fixed by screw or the like. However, in order to bind the battery stacked member by the binding bars 224, it is necessary to more strongly press the battery stacked member by the jig JG than binding the battery stacked member by the binding bars 224. As a result, when the pressing by the jig JG is released, as the battery stacked member is swollen a little, it happens that fixing positions of each of the bus bar slips. Therefore, a structure to maintain a connecting state, for example, bus bars having enlonged circle holes or track shape holes is necessary. Further, in this way, it is necessary to maintain the pressing by the jig JG until fixing of the bus bars is completed, and as time period of pressing by the jig JG is long, productivity is decreased.